Large Hurricane Gaston Prompts Tropical Storm Watch for Azores

Large Hurricane Gaston starting moving more quickly toward the northeast on Wednesday and it prompted a Tropical Storm Watch for some of the Azores.  The Tropical Storm Watch includes Flores, Corvo, Faial, Pico Gracsiosa, Sao Jorge and Terceira in the Azores.

At 8:00 p.m. EDT on Wednesday the center of Hurricane Gaston was located at latitude 35.6°N and longitude 46.5°W which put it about 1000 miles (1610 km) west of Faial in the Azores.  Gaston was  moving toward the northeast at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 969 mb.

Hurricane Gaston has a large circular eye with a diameter of 35 miles (55 km).  The eye is surrounded by a nearly complete eyewall, although the eyewall is thinner in the southwestern quadrant.  Winds to hurricane force extend out about 45 miles (70 km) from the center.  Hurricane Gaston has characteristics of an annular hurricane and the surrounding rainbands are mainly comprised of showers and shallow clouds.  The upper level divergence is inhibited over the southwestern past of the circulation, but divergence is still occurring north and east of the center.

Hurricane Gaston will be moving through an environment that will become increasingly unfavorable.  It is currently over water where the Sea Surface Temperature (SST) is near 27.5°C, but it will be moving over cooler SST during the next few days.  An upper level trough is producing southwesterly winds which are causing vertical wind shear.  The strength of the upper level winds is expected to increase.  The combination of cooler SSTs and more wind shear will weaken Gaston during the next few days.

Hurricane Gaston is being steering toward the northeast by the westerly flow in the middle latitudes.  That general motion is expected to continue.  On its anticipated track Hurricane Gaston could reach the western Azores within 48 hours.  It is expected to weaken below hurricane intensity by that time.  Because of its large size, Gaston could bring wind and rain to many of the Azores.